A data logger based on 8051 microcontroller has been implemented in this project to measure the solar radiation, temperature and charging current. Development of a low-cost data logger can easily be made and easily be used to convert the analog signal of physical parameters of various test or other purposes of engineering. By using a suitable program code it can be used to read the value digitally with a PC. Our aim is to provide with a module and a software package when installed in a computer, one can remotely acquire and monitor several numbers of the same or different types of signals sequentially at a time. Signals obtained from various sensors have been effectively conditioned. Now interfacing these signals using ADC with the Bluetooth module port of a computer satisfies the very goal of data acquisition. Proposed system provides better performance and has low cost, versatile, portable.